The predictive value of the neutrophil/platelet ratio on in-hospital adverse events and long-term prognosis in patients with coronary artery disease after percutaneous coronary intervention and its possible internal mechanism.

The neutrophil-to-platelet ratio (NPR) is considered to be an indicator of inflammatory status. The value of the NPR in predicting in-hospital adverse events (AEs) and long-term prognosis after percutaneous coronary intervention (PCI) in coronary artery disease (CAD) patients has not yet been reported. Meanwhile, the mechanisms behind its predictive value for long-term prognosis remain unreported as well. The study retrospectively enrolled 7284 consecutive patients with CAD undergoing PCI from January 2012 to December 2018. Multivariable logistic regression analysis, multivariable Cox regression analysis, Kaplan‒Meier (KM) curve analysis, restricted cubic spline (RCS) curve analysis, and sensitivity analysis were used in the study. All-cause death was the endpoint of the study. According to the median value of the NPR, the patients were divided into two groups: the high group (NPR ≥ 0.02, n = 3736) and the low group (NPR < 0.02, n = 3548). Multivariate logistic regression analysis demonstrated that a high NPR was a risk factor for in-hospital AEs [odds ratio (OR) = 1.602, 95% CI 1.347-1.909, p = 0.001]. During a mean follow-up period of 3.01 ± 1.49 years, the multivariate Cox regression analysis showed that a high NPR affected the long-term prognosis of patients (HR 1.22, 95% CI 1.03-1.45, p = 0.025) and cardiac death (HR 1.49, 95% CI 1.14-1.95, p = 0.003). The subgroup analysis showed that the NPR was affected by age and sex. The mediation analysis identified that the effect of the NPR on long-term outcomes is partially mediated by serum creatinine (Scr) and triglycerides. The NPR may be a convenient indicator of in-hospital AEs and poor long-term and cardiac outcomes in CAD patients. It might have impacted prognosis through effects on kidney function and lipid metabolism.